2 Answers
2

Open TeXworks, choose Edit -> Preferences... in the menu and go to the Typesetting tab. In the Processing tools section, click on the little + button to add a new entry. In the dialog window, you have to type in the following values:

Repeat this step to add LuaLaTeX:

Now, you will be able to choose LuaTeX/LuaLaTeX from the dropdown box next to the green button.

UPDATE
In some cases, the argument -synctex=1 may cause trouble. Try replacing it by $synctexoption in this case or leave it out completely.

In preferences, composition, processing tools, you can add your preferred engines here in case luatex or lualatex ...
For Linux it's like that and also for os x I think for windows it's the same.
You can see the command line for others engines, and after you can adapt for luatex and windows.
First the command line ( /home/yourname/TeXLive/bin/i386-linux/luatex) then options, $synctexoption (to sync with the pdf) and $fullname.